Iranian police have killed six drug traffickers and seized five tons of opium in armed clashes in the country's east, the Iranian media reported on Sunday.

The police operation in the Sistan-Baluchestan province on the border with Pakistan was launched on Saturday afternoon and lasted several hours. There have been no reports of casualties among the police, the media reported.

Drug traffickers use the territory of Iran for the smuggling of drugs largely produced in Afghanistan.

According to Iranian police, about 30% of narcotic drugs produced in Afghanistan and Pakistan are smuggled into Iran, of which 50% remain in the country and the remaining part is brought to other countries.

From April 2008 to January 2009, Iranian police killed 120 drug traffickers and drug dealers and seized over 30,000 tons of drugs. A total of 19 Iranian police and border guards were killed in armed clashes with drug traffickers and drug dealers over that period.

The Iranian authorities spend about $600 million a year on the fight against drug trafficking.